In general, a table has a certain height and cannot be adjusted in height. Due to the limited height of use, its practicality is reduced greatly, and it is not ergonomic. In order to meet the height requirement of the table for different users, many manufacturers have developed tables with lifting mechanisms (such as conference tables, etc.). At present, there are two ways to lift office table tops (such as conference tables) and dining tables used for hospital beds. One is realized by using a gas spring in cooperation with a locking mechanism. The table top is pulled to a certain height by an external force and then fixed by the locking mechanism. The other is realized by using a gas spring in cooperation with a serrated device. This lifting way is performed only at a predetermined position of the serrated device. The above two ways have certain limitations. In the process of actual use, the table top is not fixed firmly and often shakes. Moreover, the phenomenon of jamming is likely to occur during the lifting operation. The guiding effect is poor. The table top may rotate relative to the base, which brings a lot of inconvenience to users.